Drum lifter for industrial trucks



Sept 1954 6 L. c. SHRAMEK 2,689,663

DRUM LIFTER FOR INDUSTRIAL TRUCKS Filed Feb. 5, 1952 Patented Sept. 21 1954 UNITED STATES PATENT OFFICZE DRUM LIFTER FOR INDUSTRIAL TRUCKS Ladd C. Shramek, Stevensville, Mich. Application February 5, 1952, Serial No. 270,030

8 Claims. I I a r 1 This invention relates to a lifting and transporting mechanism and is especially useful in connection with material handling apparatus such as transporting and elevating trucks. More particularly, the invention relates to a lifting and moving device which may be attached to a common elevator truck without modification and which will enable such truck to transport barrels, drums and other similar containers.

While various mechanisms have been designed for the elevation and transportation of barrels and the like, the devices have generally fallen short of the needs of industry in that they are excessively complicated, or are limited to the handling of particular shapes of containers. It is, therefore, a major aim of my invention to provide a device of the type mentioned which is simple and inexpensive in construction and which is also adaptable for use with almost all drums now in use.

A further object of my invention is to provide a container lifting and transporting device which may be attached with a minimum of effort to any of the common commercial elevator trucks now in general use.

A further object of the invention is to provide a container lifting mechanism which may be readily adjusted to handle containers of diiferent types.

Yet another object of my invention is to provide a hammer lifting and transporting device wherein theweight of the container supplies a major, portion of the gripping force, by virtue of which featureany tendency for heavy containers toslip and fall is overcome.

Other objects and advantages will appear to those skilled in the art from an inspection of the following detailed description of the attached drawings.

On the drawing:

v Figure 1 is a view in side elevation of an elevating and transporting truck provided with the lifting mechanism of my invention;

t Figure 2 is an enlarged broken cross-sectional view of the internal parts of my gripping mechanism; and.

2 means of well known controls not shown herein. At the right end of the lift forks 3 is positioned the lifting device of my invention, shown holding a barrel 6 of a type in general use.

In the embodiment of my invention shown, a hollow-hook-shaped column or housing 5 is provided. At the tip of the hook a backing plate I is firmly aifixed to the column by means of a throughbolt 8. An upwardly angled holding tooth 9 is formed on the backing plate 1, which provides one wall of a guideway generally indicated at I0. Located at the other side of the guideway is a pivoted eccentrically shaped pawl or cam I2 which is rotatably mounted upon a stationary stud II. As shown in Figure 2', the pawl I2 is provided with teeth I3 which are sloped upwardly and which are arranged on an arc of increasing radius about the stud II in a counterclockwise direction. The stud II, which Figure3 is, anenlarged cross-sectional view taken as indicated by the line III-III of Figure 1.

As shown on the drawings: The power-operated elevating and transporting truck I is of well known construction and is provided with elevator colums 2 upon which the usual lift forks 3 are mounted for vertical movement. An operator is seated at 4, from which position he operates the truck and elevator by forms the pivotal axis for the pawl II2, is'positioned at a point vertically lower than the point of contact between the teeth I3 and the container I5. This relationship, along with the upwardly sloping shape of the series of serrations formed by the teeth I3 and the eccentric mounting of the pawl I2 provides a self-energizing grip action on the load. Thus the heavier the load 6 the greater will be the tendency of the pawl I2 to rotate in the clockwise direction, and due to the increasing radius of the teeth I3, the gripping force.

While in the embodiment illustrated, the pawl or cam I2 is provided with upwardly sloping teeth I3, it is apparent that'modification may be made without departing from the scope of my invention. For example, the teeth I3 may be replaced by a knurled or otherwise roughened surface which would provide sufiicient frictional force against a container rim to cause self-energization of the eccentrically shaped pawl I2. Further, it would be feasible in some installations to remove all surface roughness from the pawl and rely entirely upon surface friction and the eccentric shape of the pawl I2 to force the container against the holding tooth 9 by cam action. Similarly, the tooth 9 could be replaced in some light-load uses with a roughened or smooth surface.

The pawl I2 is provided with a radially disposed operating lever I4. A spring I6 is attached at I! to the housing 5 and at I8 to the operating lever I4. A control cable I9 passes over a pulley 20 and is attached to the operating lever I4 by any well known fastening means as shown at 2 I.

The pulley 20 is pivotally secured to an eye bolt greater will be the '22 which is in turn securely fixed to the housing 5. A stop pin 23 is fixed to the housing and cooperates with a channel 24 which is so shaped that the pawl l2 may in no case be rendered unserviceable by excessive oscillation in either direction about the stud II.

A cover plate 25 with a hole 26 for the passage of the cable [9 is screwed by means of screws 21 to the housing, 5. This cover provides a method of easy access to. the internal mechanism and also prevents foreign matter from accumulating in the housing 5.

When the device is not in operation, the pawll2 will be held in an imperative: position by thespring I6. At this time the stop pin 23 will abut the pocket at the right hand end of channel 2i. When it is desired to transport. a container, the columnar housing 5 is lowered over the edge thereof so that edge of the container enters the guideway Ill. The operator then pulls the cable [9; This action. rotates the pawl I22 through the cont-rot lever; I54. in. a clockwisedirection, engaging the: teeth ts with the rim or flange of the. container andcompressing such. flange: against the tooth 9. The container may then. be: litted and moved about. As will. be seen: from Figure l, the base of the container will rest against the end: of the elevator iork 3 to-prov-ide. lateral support, as: at 561'.

order to release the container from the gripping; mechanism,. the operator merely lowers the container to. the ground When the container touches the: ground, continueddownward. movementoi the forks 3 will cause upward movement of the rim of. the container relative to. the pawl I121 thus; removing the load thereilrom. As soon as the. load has.- been removed. the spring L5. will automatically return. the pawl 12. tov its. normal inoperative position. I

The columnar housing 5. is telescopically mounted in a sleeve 28- which is in. turn. fixediy secured to a base. plate. 29,. preferably by welding. supports 38 arerigidly secured between the sleeve 23 and the base. plate 29 to. provide greater rigid.- ity' to the structure. The sleeve 25 is slotted at. iii. and isprovided with a. friction clamp 32 which may be. tightened theconventi'onal manner by means oi handle 33'. In. use, the effective height of; the. columnar. housing 5 may be adjusted by sliding. it vertically in the sleeve 28? until the proper height is reached and then securely clamping, it in adjusted position by means of the. clamp 32.

A further important feature of my liftin mechanism is the arrangement provided for the attachment of the device to the lift fork of the elevator The base plate 29 is provided with downwardly and inwardly turned sidefianges: 34' to' provide support portions upon which the liiting device may be rested when not in use. When it is desired to attach the lifting mesh-- a-nismto the elevator truck, the elevator is loweredto its lowermost position theforks 3 are movedforward underthe base plate 29 The underpiate 35 is then drawn up by means ct handle 35 to: securely clampthe litting mech anism tothe iorlss 3-. Provision of support 3% allows the attachment, of the lifting: mechanism to the forks 3 without the necessity of first hoiste ing' the lifting mechanism into: position. Since the lifting mechanism is of quite heavy materiah in order to withstand the loads imposed by very heavy containers, the elimination of any need for manually handling the device itself is a great advantage.

As will be seen from the foregoing description, there is provided a durable and extremely useful lifting mechanism. While the mechanism is simple it will nevertheless handle large loads in any type of open or closed container having an upstanding peripheral rim or flange. The mechanism of my invention is readily adapted to various sizes of containers by adjustment of the clamp 32 to vary the height of the column 5 and. by the automatic adjustment of the: pawl I2 to container rims of various thicknesses. A minimum of room at the top edge of the container is necessary to obtain adequate gripping. This allowsthev lifting, mechanism to be used with unopened drums and closed containers provided with flanges projecting upwardly from the'cover of the container.

It will be understood that modifications and variations may be effected without departing from the scope of the novel concept of the present invention.

I claim as my invention:

h. Aliiting mechanism. for use. with transporting trucks or the: like comprisingv a. hook-shaped housing; having therein a. guideway slot, a-holdi-ng member on. one. side of. said guideway slot, agripping pawl on the other side oi said guideway slot, means normally biasing said pawl. away from said slot, and. an. operating; mechanismv for engaging said. gripping pawl with a container. to be. lifted, saidv gripping pawl. having, upturned teeth whereby the container is held between said holding member and. saidgripping pawl. by the. weight of the. container itself.

2. A. lifting mechanism for use: with transport-- ing trucks. or the like comprising a hook-shaped housing having a. substantiallyvertically disposed guideway slot therein, a holding. tooth onone. side of said guideway, an oscillatory gripping. pawl on the other side of said guideway, means. normally biasing. said. pawl away from said tooth and. an operating mechanism for oscillating said gripping, pawl into contact. with a. container. placed within said guideway slot. whereby the container is held by its own weight between. said holding, tooth and said gripping pawl as the housing is lifted and is automatically released therefrom by movement of said container upwardly relative to said housing when said housing is lowered to place the. container on a support.

A lifting mechanism for use with transporting trucks' or the like comprising a hook-shaped housing, having a substantially vertical guideway slot therein, a holding surface" on one side ofisaicf gui'd'sway slot, eccentrically mounted oscil latcry gripping cam on the other side of said guideway slot, means for moving said housing vertically" relative to a container in order to place an upstanding lip of the latter within said. slot and mechanism for oscillating the eccentric gripping cam into engagement with saidlip, saidongagement being aided at least in part by downward forces applied to the gripping cam by the lip due to the weight of the container, whereby the: container is held betweensaid holding surface and said gripping cam.

4. In a lifting attachment for use with: transporting trucks or the like. having elevator forks, a columnar housing. having: a. substantially vertical guideviay slot therein, a holding tooth rigidly positioned at. one: side of said. guideway slot, a

gripping pawl mowabl'y positioned at the other side of saidguideway' slot, an operating mecha' nismadapted to engage said gripping pawl the edge of a container located within said guideway slot, a sleeve telescopically supporting said columnar housing for vertical movement relative to said container to position said container in said slot, and an elevator fork-engaging base adapted to be clamped to the elevator fork of said transporting truck.

5. A lifting mechanism for use with transporting trucks or the like comprising a housing having a substantially vertically disposed guideway slot therein, a holding tooth on one side of said guideway slot, an oscillatory gripping pawl on the other side of said guideway slot, means normally biasing said oscillatory gripping pawl in a direction away from said holding tooth, and operating mechanism for oscillating said gripping pawl against the force of said biasing means in the direction of said holding tooth whereby said gripping pawl will contact a container rim located in said guideway slot to hold said rim against said holding tooth and to be held in turn in contact with the rim by the weight of the container.

6. A lifting mechanism comprising a housing having a guideway slot therein, a movable gripping member positioned at one side of said guideway slot, and movable across the slot against the influence of a biasing means and an operating arm for overcoming said biasing means and actuating said gripping member into engagement with a container placed within said guideway slot, said gripping member having a self-energizing movement whereby the container is firmly maintained in said slot by its own weight acting on said gripping member.

7. A lifting mechanism for use with transporting vehicles, comprising'a hook-shaped housing, having a substantially vertically disposed downwardly opening guideway slot therein, an upwardly angled holding tooth forming one wall of said guideway slot, an oscillatable, eccentrically mounted gripping pawl pivoted at the other side of said guideway slot and at a point vertically lower than said holding tooth, biasing means for normally retaining said gripping pawl in an inoperative position, operating means for overcoming said biasing means and engaging the gripping pawl with a container positioned in said guideway slot and adjustable mounting means whereby said hook-shaped housing may be vertically adjusted to accommodate containers of different heights.

8. A lifting mechanism for use with transporting and elevating trucks, comprising a columnar housing having a substantially vertically disposed guideway slot therein, a holding member forming one wall of said guideway slot, an oscillatable eccentrically mounted gripping member pivoted at the other side of said guideway slot and at a point vertically lower than said holding member, means for normally retaining said gripping member in an inoperative position, operating means for overcoming said retaining means, a support for said columnar housing, said support including downwardly turned flanges providing spacing means between a floor and said support whereby the lifting mechanism may be attached to said truck without lifting.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,760,885 Prelesnik June 3, 1930 2,250,475 Ernst July 29, 1941 2,272,447 Traxel Feb. 10, 1942 2,364,493 Ulinski Dec. 5, 1944 2,399,360 Lacey Apr. 30, 1946 2,447,300 Williams Aug. 17, 1948 2,558,388 Richardson June 26, 1951 2,620,937 Halloran Dec. 9, 1952 

